Anti-social children are commonly characterized as unconcerned about others' needs, lacking in responsibility and appropriate guilt. This study investigates individual differences in emotion regulation, social competence, and empathy in young children who differ in risk for disruptive behavior disorders. A major goal is to identify subtypes of young children, all with early externalizing problems, who later differ in styles of emotion regulation, types of symptoms and syndromes, and capacity for responsible interpersonal behavior. Patterns of emotion, behavior, autonomic function and social-cognition in hypothetical and real situations of interpersonal conflict and distress were examined in aggressive, disruptive, difficult-to manage preschool children. Eighty children were seen first at 4-5 years and again at 6-7 years. The present report focuses on emotion regulation (facial and autonomic activity) assessed during negative mood induction, and prediction of concurrent and subsequent problems. Facial expressivity during negative mood induction was used to identify three emotion regulation groups: inexpressive, modulated expressive and highly expressive of negative emotion. Inexpressive 4-5 year olds had the highest heart rate, lowest vagal tone, and least ANS change during the induction. Highly expressive children had the slowest heart rate, highest vagal tone, and most ANS change. Both the inexpressive and highly expressive groups had more externalizing symptoms than the modulated group at 4-5 years, and also at follow-up at the end of first grade, when psychiatric interviews were conducted with both mothers and children. Inexpressive children had more depressed and anxious symptoms at follow-up. The findings underscore the complexity and diversity of preschool age behavior problems that may appear similar in terms of outward expression. Hence, they suggest one promising approach for examining how different underlying or associated patterns of emotion regulation may influence the development of different forms of serious behavior disorders over time.